The point is that DBIC already does all that testing for you with regards to how a given DBMS will work. All you care about is making sure that you make the right calls to DBIC. To test that, you can go ahead and use DBD::Mock
to test your SQL. Alternately, you could work with the DBIC folks - they've almost got a testing framework for use with DBIC applications all done.
The point is that you use a tool so that you don't have to maintain a given subsystem. If you don't have to maintain it, you don't have to test it. So, you can test a single RDBMS (mysql or pg, for example) and be reasonably certain that it will all work in others.
My criteria for good software:
- Does it work?
- Can someone else come in, make a change, and be reasonably certain no bugs were introduced?